Quick correction mechanism for a seconds hand of a timepiece

ABSTRACT

This invention relates to a quick correction mechanism for the seconds hand of an electronic timepiece. The object is to provide a unique mechanism residing in such a point that by operating a manual control means, preferably shaped into a special stem other than the regular winding stem, to perform a number of reciprocations corresponding to the number of seconds to be corrected, a drive coil is energized to have a corresponding number of drive current pulses which are then utilized to rotate the rotor of a step motor by a corresponding angle. This rotational movement is transmitted through mechanical transmission means to the conventional seconds hand gear which thus corrects correspondingly the position of the seconds hand.

United States Patent 1191 Naikaido-et al. I

[ QUICK CORRECTION MECHANISM FOR A SECONDS HAND OF A TIMEPIECE [75] Inventors: Akira Naikaido, Tokyo; Mitsuo Onda; Takayasu Machida, both of Saitama; Fumio Nakajima, Tokyo; Takashl Toida, Tokyo; Yoshihiko Yanagawa, Tokyo, all of Japan.

[73] Assignee: Citizen Watch Company Limited,

Tokyo, Japan [22] Filed: Jan. 5, I972 [21] Appl. No.: 215,515 I [52]- U.S. Cl .L 58/23 D, 58/34, 58/855 [51] Int. Cl .7 G04c 3/00 [58] Field of Search 58/23'R, 23 A, 23 D, 34, 58/50 R, 85.5; 307/225 R; 328/48 [56] References Cited UNITED STATES PATENTS 3,363,410 1/1968 1111311215111"; ..58/23-ACX 6/1972 Bergey et al 58/85 5 1111. 3,810,354 1451 May 14,1974

Primary Examiner-Richard Bjwilkinson Assistant Examiner-Edith Simmons Jackmon Attorney, Agent, or Firm-Frank .l. Jordan 57] ABSTRACT This invention relates to a quick correction mechanism for the seconds hand of an electronic timepiece.

The object is to provide a unique mechanism residing in such a point that by operating a manual control means, preferably shaped into a special stem other than the regular winding stem, to perform 'a number of reciprocations corresponding to the number of seconds to be corrected, a drive coil is energized to have a corresponding number of drive current pulses which are then utilized to rotate the rotor of a step motor by a corresponding angle. This rotational movement is transmitted through mechanical transmission means to the conventional seconds hand gear which thus corrects cor espondingly the position of the seconds hand.

10 Claims, 9 Drawing Figures PATENTEUIIAYMIBH 3310.35 I SHEEI 3 or 3 FIG. 6 RESET oFF F l G. 8

O 1 BH1 8 3 Tn-1 (V Tn k DC] W F I G. 7

RESET OFF 1 An O Q 3 TH] L K 8 g l QUICK CORRECTION MECHANISM FOR A SECONDS HAND OF A TIMEPIECE This invention relates to a quick correction mechanism for a seconds hand of a timepiece.

It has been highly and sincerely desired by those skilled in the art to provide an efficient mechanism adapted for performing quickcorrections of the seconds hand in a battery-powered timepiece, especially those having a crystal oscillator and a pulse-driven motion converter such as, for instance, pulse motor.

In the conventional art, mechanical means such as cams, levers and the like members are mainly relied 7 upon for performing the correction of the seconds hand position to show the correct time display. In this case, a rather heavier finger effort must be applied to the winding stem for pushing-in thereof. In addition, the correcting job is rather defective in such that the seconds hand cam only be corrected to a certain or other specifically selected position.

The main object of the invention is to provide an efficient quick correction mechanism capable of obviating the aforementioned drawbacks inherent in the prior art.

' A further object is to provide an improved seconds hand corrector, capable of operating substantially electronically and each time for correction of just a onesecond 'of time.

Still a further object is to provide an efficient and convenient seconds hands corrector, capable of performing a desired series of correcting steps, and at any time to any hand position as desired. I

These and further objects, features and advantages of the invention will become more apparent as the description proceeds by reference to the accompanying drawings illustrative of several-preferred embodiments of the invention. ln the drawings:

F IG. 1 is a plan view, partially being broken-away and sectioned for display of several inner working parts, of an electronic watch embodying the principles of the present invention.

FIG. 2 isa schematic arrangement plan of several main working blocks of the watch movement contained in the watch shownin FIG. 1,'the present plan being, however, shown on a substantially enlarged scale relative to that employed in FIG. 1.

FIG. 3 is a perspective view of a motion converter unit employed in the electronic watch embodying the principles of the invention.

' FIG. 4 is a block diagram showing a preferred em-- bodiment of the electronic circuit section of the motion converter.

FIG. 5 is a block diagram showing a further embodiment of the electronic circuit section employable in this invention.

FIGS. ,6. and? represents several volta'ge cures as appearing at several parts of the electronic circuit according to this invention.

F lGS.- 8 and 9 represent two embodiments of a reset circuit employable in the present invention.

Referring now to the accompanying drawings, especially F IG. 1 thereof, numeral 1 represents generally an electronic watch which is fitted with a second hand quick corrector according to thisinvention. This watch is fitted with a first or conventional winding stem 2 which is mounted in watch casing la and arranged axially movable and rotatable as known per se.

2 Numeral 3 represents a second stem formed into a push button as shown and slidably mounted through the same watch casing la and adapted for cooperation of the electronic circuit section which constitutes the main working one of the improved watch 1, as will be more fully appeaed as the description proceeds.

Numeral 4 represents the movement of the watch 1. A movable contact 6 which is mounted rigidly on the free end of a spring strip'8 the root end of which is fixedly attached to the inside peripheral wall surface of the watch casing la by soldering, set screws or the like conventional fixing means, although not specifically shown only for the simplicity of the drawing.

The inner end of the second stem 3 is shaped so as to represent an enlarged end 3a with whichthe spring strip 8 is normally in pressure contact. A stationary contact 7 is fixedly on the upper surface of the watch movement 4. Although not shown, as the fixing attaching means for the positioning of the stationary contact, soldering, studding, screwing or the like conventional technique may be relied upon. As will be more specifically described'hereinafter, the stationary contact 7 may be replaced by the pressure-receiving part of a pressure-responsive semiconductor S6.-

Numeral 51 represents a battery block which is fixedly, yet detachably mounted inthe movement 4 and 52 denotes a conventional crystal oscillator block which is detachably mounted in the movement. Since this kind of the oscillator is highly well known among those skilled in the art, it isshown only schematicallyelement known per .by its general outline configuration. Numeral 53 represents an electronic circuit block comprising an oscillator stage, a frequency divider stage and a drive stage, as will be more fully described'hereinafter, said circuit A condenser 54 is mounted detachably in the movement 4 for serving as frequency adjuster for the oscillator stage.

Numeral 55 represents a U-shaped core piece having a parallel pair of legs 55a and 55b, coil winding 56a and 56b being wound on these legs 55a and 55b, respectively. The core' piece 55 is held firmly in position on the movement 4 by means of a plurality of set screws, commonly denoted by a single reference numeral 100. i

Numeral 57 represents a rotatable wheel which is concentrically united with a sprocket wheel 58. Numeral 59 denotes a springystop pawl, the free end thereof being normally kept in meshing with one of the peripheral teeth on the sprocket wheel.

A seconds hand wheel 60 constitutes a member of the conventional gear train of the watch. Numeral 61 represents a seconds hand which is rotatable in unison with the wheel 60 through anarbor 101 carryingsaid seconds hand. 62 represents a pressure spring acting upon the seconds hand wheel 60.

In FIG. 4, numeral 9 represents an input terminal which is connected with a time base oscillator such as crystal oscillator or a tuning fork vibrator, so as to receive therefrom a series of standard time base signal pulses which have been provided by frequency division of the electrical output signal delivered from the said crystal oscillator or tuning fork vibrator, not shown.

Numerals 10, ll, 12 and 13 represent successive frequency divider stages which are connected one after block 53 being detachably positioned in the movement 1 .4.

another and so designed and arranged that each of these stages receives the output frequency of the preceding stage and divides frequency by two.

Frequency divider represents two separate and different signal outputs Al and B1. In the similar way, frequency dividers 11, 12 and 13 represent each two separate outputs signal A2; B2, Arrl; Bn-l, An and En, respectively. 14 and 16 represent pulse shaper circuits, although shown in a highly simplified and schematic way with respective blocks. and 17 represent drive circuits for the pulse motor to be described. 10R, llR'and 12R represent respective reset terminals of frequencyv dividers 10, 11 and 12 and connected to a common reset line 18. 19 and 21 represents two separate drive coils of said pulse motor and connected electrically with each other and with said drive circuits, as shown. Arrows and 22 hint respective current passage directions. A schematically shown rotor 23 belongs also to the pulse motor and is adapted for being driven by the-magnetic fluxes emanating from these drive coils l9 -and*2l. Although not specifically described, the plurality of circuit sections, terminals, coils and the like described so far in connectionwith FIG. 4, are electrically connected one after another as shown, as most clearly be understood at a glance thereof.

In FIG. 5,24 represents generally a pair of input terminals adapted for receiving a series of time base signal.

pulses from the time base oscillator such as crystal oscillator or tuning fork vibrator, as the case may be as before. Numerals 25, 26, 27, 28 and 29 represent respective frequency divider stages designed and arranged, so as to divide the frequency of the foregoing stage value .by two, as before. 30 and 32 represent AND-circuits and 31 and 33 demonstrate respective inverters. 34 shows the drive coil for the rotor 36 of the pulse motor. Arrows generally shown at 35 hint the alternatingly changing directions of the current passage through the pulse motor which comprises a rotor 36' only schematically shown and adapted for being driven under the influence of magnetic fluxes provided by the drive coil 34. I i

In FIG. 9, a pressure-sensitive semi-conductor 41 is used in place of a terminal.

Next, the operation of the aforementioned embodiments, together with additional description.;of minor remaining structure, will be given hereinbelow:-

Under normal operational conditions drive coils l9 and 21 are impressed alternatively with drive voltage pulses having a frequency of IV Hz and a proper pulse width or duration period, so as to rotate the rotor 23 of the pulse motor comprising said drive coils, in a certain predetermined direction at a certain speed.

In the case of a modified arrangement shown in FIG. 5, the sole drive coil 34 is impressed in an alternatively way with a series of voltage pulses having a frequency of 1 Hz and of a proper pulse width or pulse duration period, so as to rotate the rotor 36 of the pulse motor comprising said drive coil 34, in a certain predetermined direction.

In either case shown in FIGS. 4 or 5, the rotor 23 or 36 is given a drive pulse per each second. Thus, motion is transmitted from the rotor 57 shown in FIG. 3 which is similar to that denoted 23 or 36 shown in and described in connection with FIGS. 4 or 5, respectively,

a unitary pinion 105 to the seconds hand wheel 60 meshing therewith, thence through arbor 101 to the seconds hand 61 which thus performs a pulsative rotamovement of the hand 61 is assumed by the provision of a sprocket wheel 58 cooperating with the stop pawl 59. Although not shown, the root end of this stop pawl 59 is fixedly, yet adjustably mounted on a certain stationary member, preferably the conventional pillar plate, of the movement 4, by means of an adjustable fixture shown at 106 in FIG. 3. This stepping motion will be further transmitted through a unitary pinion 107 with the wheel 60 to the conventional time display gear train, not precisely shown.

When it is desired to advance the seconds n being a certain integer, the second stem 3 shown in FIGS. 1 and 2 is pushed in n times, so as to on-off control the mating contacts 6 and 7 in a corresponding number of reception.

Now it is assumed that the prefinal frequency divider stage FFnI- has binary outputs: An l l and En 1 0 and a resetting operation is initiated under these conditions in FIG. 4. It is further assumed that the direction of resetting is towards the conditions:

Bn l 0). Under these conditions, frequency divider stages FFl, FF2, FFn l are not reversed in their respective state by the resetting operation. By. making the resetting to off from these conditions, the stage FFn- I will rapidly reverse its state at a high frequency FFl, an output Tn- 1 representing a positive trigger pulse 38 from Bn 1. When the frequency divider stage FFn has been designed to reverse by such phenomenon, the FFn will convert its operating state, and, as an example, 0 becomes 1 at An and 1 becomes 0 at Bn, thereby a positive trigger pulse Tn will be delivered from terminal An, which is then processed in the signal shaper 14 and thence conveyed through drive circuit 15 to drive coil 19, current thus flowing therethrough in the direction of arrow 19 so that'rotor 23 makes a rotational one step. By selecting a proper overall gear ratio, the seconds hand 61 can perform a l-second step.

For better understanding, reference may be had to FIG. 6 showing several related pulse wave curves.

Next, referring to FIG. 7, resetting operation is assumed to be taken under the conditions of: An l 0; En l O.

In this case, all the stages FFl, FF2, FFn I, will work so as to be:

delivered through Bn and thus a drive pulse will begiven to the drive coil so that the motor makes a rotational step corresponding to the sole drive pulse. Therefore, the seconds hand 61 will make an advance movement just by a second.

According to the arrangement suggested by the present invention, by manipulating the second stem so as to make an axial reciprocation, the seconds hand can perform a one-second advance step, irrespective of the conditions in the peripheral frequency divider stage FFn l. By nth repetition of the above manipulation, the seconds hand can advance n seconds.

Similar operation and effect can be obtained by use of the arrangement shown in FIG. 5. In this arrangement, the drive current flows through the sole drive coil in an alternating way, but operation of the seconds hand is similar to that appearing in the foregoing arrangement shown in FIG. 4.

In the present embodiment shown in FIG. 5, the outputs from the respective frequency divider stages are fed to the AND-circuits 30 and 32 as the inputs thereto. The number of connecting terminals to these circuits 30, 32 will decide the width of the drive voltage pulse.

In the modified arrangement shown in FIG. 8, the

'reset mechanism comprising the second stem 3 and switch contacts 6, 7 is coupled with a first frequency divider stage of bipolar transistor type comprising transistors trl and tr2 connected as shown therein. The operational results will be substantially similar as before.

, arranged to cooperate with the actuating end 3a of the stem 3.

When pressure is transmitted from the end 3a of stem 3, the diode 40 becomes conductive, so that the collector-emitter passage of transistor 41 being shortcircuited. Therefore, the similar effect as described in connection with the foregoing embodiments can be attained. ln'this FlG.-9, the chain-dotted parts are similar to those shown in FIG. 8. I 1

From the foregoing description, it would be clear that the circuit shown in the foregoing can'be comprised of bipolar-1C, MOS-[C or the like composite circuit elements. lt'would be self-explanatory that the invention can equally be applied to the clocks.

In the foregoing description, the seconds hand correction has been described in the case of advancement of the hand: But, it is naturally n'ecessary'frequently to retard the hand; In this case, second stem 3 is continuedly depressed for a certain predetermined period, so' as to keep the hand inits stopped position. This operation will invite in effect the corresponding retardation in the positive of the hand. Upon completion of this hand-stoppage operation, the regular steppingly performed correcting operation can, when necessary,

be adopted. I I

The embodiments of'the invention in which an exclusive property or privilege is claimed are as follows:

1. An electronic timepiece. comprising a series of frequency divider stages connected in sequence for obtaining timing drive pulses, said series-connected stages forming a pulse frequency divider, a reset circuit connected with at least some of the frequency divider stages and excluding the final stage of said frequency divider, said frequency divider stages eachreceiving the output frequency of the preceeding stage and dividing it by two, and an on-off control means controlling said reset circuit. I

2. An electronic timepiece, comprising a series of frequency divider stages connected in sequence for obtaining timing drive pulses, said series-connected stages forming a pulse frequency divider, a reset circuit connected with at least some of the frequency divider stages and excluding the final stage of said frequency divider, an on-off control means controlling said reset circuit, a plurality of AND gates with inputs connected to the outputs of said frequency divider stages, and motor means with drive coils connected to the outputs of said AND gates.

3. An electronic timepiece, comprising a series of frequency divider stages connected in sequence for-obtaining timing drive pulses, said series-connected stages forming a pulse frequency divider, a reset circuit connected with at least some of the frequency divider stages and excluding the final stage of said frequency divider, an on-off control means controlling said reset circuit, and contact means between a terminal of said reset circuit and one end of said on-off control means, said contact means comprising a pressure-sensitive semiconductor.

4. An electronic timepiece according to claim 1 including contact means between a terminal of said reset circuit and one end of said on-off control means.

5. An electronic timepiece according to claim 1 wherein said frequency devider stages comprises bistable circuit means.

6. An electronic timepiece according to claim 2 wherein said motor means comprises pulse controlled step motor means.

7. An electronic timepiece according to claim 2 including amplifying means between said AND gates and said drive coils. I

8. An electronic timepiece according to claim 1 wherein said onoff control means comprises pushbutton switching means.

9. An electronic timepiece according to claim 1 including oscillatingmeans for applying regularly-spaced pulses to said frequency divider.

10. An electronic timepiece according to claim 2 including signal shaping means connected between said motor means and the output of said frequency dividen I "UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,810,354 Dated y 7 Invntorm Akira NIKAIDO et al- It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the headin correct the spelling of the first inventor's name to read --Akira Nikaido--.

Signed and sealed this 1st day of October 1974.

I (SEAL) McCQY M. GIBSON JR. (2. MARSHALL DANN Attesting Officer Commissioner of Patents FORM PO-IOSO (10-69) USCOMM DC 6o376 P69 u,s. GOVERNMENT PRINTING omca: I969 o3sa-au UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. ,810,354 Dated 14 1974 Inventofls) Akita IKAIDO et al. I

It is certified that error appears in the aboveidentified patent and that said Letters Patent are hereby corrected as shown below:

1' In the heading, correct the spelling of the first inventor's name to read --Akira 'Nikaido-n Signed and sealed this 1st day of October 1974.

( EA I Attest: MCCOY M. GIBSON JR. c. MARSHALL DANN Attesting Officer Commissioner of Patents FORM PC4050 (w'59) uscoMM-oc 6O376-P69 U. 5 GOVERNMENT PRINTING OFFICE I 1969 0-355-334 

1. An electronic timepiece, comprising a series of frequency divider stages connected in sequence for obtaining timing drive pulses, said series-connected stages forming a pulse frequency divider, a reset circuit connected with at least some of the frequency divider stages and excluding the final stage of said frequency divider, said frequency divider stages each receiving the output frequency of the preceeding stage and dividing it by two, and an on-off control means controlling said reset circuit.
 2. An electronic timepiece, comprising a series of frequency divider stages connected in sequence for obtaining timing drive pulses, said series-connected stages forming a pulse frequency divider, a reset circuit connected with at least some of the frequency divider stages and excluding the final stage of said frequency divider, an on-off control means controlling said reset circuit, a plurality of AND gates with inputs connected to the outputs of said frequency divider stages, and motor means with drive coils connected to the outputs of said AND gates.
 3. An electronic timepiece, comprising a series of frequency divider stages connected in sequence for obtaining timing drive pulses, said series-connected stages forming a pulse frequency divider, a reset circuit connected with at least some of the frequency divider stages and excluding the final stage of said frequency divider, an on-off control means controlling said reset circuit, and contact means between a terminal of said reset circuit and one end of said on-off control means, said contact means comprising a pressure-sensitive semiconductor.
 4. An electronic timepiece according to claim 1 including contact means between a terminal of said reset circuit and one end of said on-off control means.
 5. An electronic timepiece according to claim 1 wherein said frequency devider stages comprises bistable circuit meanS.
 6. An electronic timepiece according to claim 2 wherein said motor means comprises pulse controlled step motor means.
 7. An electronic timepiece according to claim 2 including amplifying means between said AND gates and said drive coils.
 8. An electronic timepiece according to claim 1 wherein said on-off control means comprises push-button switching means.
 9. An electronic timepiece according to claim 1 including oscillating means for applying regularly-spaced pulses to said frequency divider.
 10. An electronic timepiece according to claim 2 including signal shaping means connected between said motor means and the output of said frequency divider. 